PETER Slipper's alleged misuse of taxpayer-funded Cabcharge dockets is now the subject of an official Australian Federal Police investigation.
The AFP today confirmed that the fraud allegations, made by Mr Slipper's former staffer James Ashby, required "further investigation".
Late last week the AFP said it had received a referral to investigate the matter.
"As part of the evaluation process for this referral, AFP investigators spoke to a number of potential witnesses and gathered information in relation to the matter," the statement read.
"As this is now an ongoing investigation, the AFP will be making no further comment on this matter at this stage. To do so could jeopardise the integrity of the investigation."
Mr Ashby launched a civil action in the Federal Court on April 21 claiming Mr Slipper sexually harassed him.
In documents lodged with the court Mr Ashby also alleged he saw Mr Slipper hand blank Cabcharge dockets to a limousine driver.
Mr Slipper continues to deny the civil and criminal allegations, and last week released Cabcharge dockets he claimed cleared him of the fraud allegations.
Mr Slipper announced on Sunday he would continue to stand down as Speaker while both the civil and criminal matters were dealt with.
News of the AFP investigation came as Labor attempted to turn up the heat on Liberal frontbencher Christopher Pyne over meetings he had with Mr Ashby in the weeks leading up to the Federal Court action being launched.
Fairfax reported Mr Pyne spent two hours socialising with Mr Ashby a month before the documents were lodged.
The Leader of Opposition Business said he met Mr Ashby on three occasions, but "on no occasion did he raise the matters canvassed in the Federal Court".
Mr Pyne also denied he sought Mr Ashby's contact details, despite Fairfax obtaining an email to the contrary.
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